There are various layers of sheeting on top to make the roof waterproof.
Sedum roof construction.
The layers work in partnership with each other to provide a whole host of benefits for the building its occupier and the environment.
On top of that we added 75mm of mixed topsoil and gravel into which the sedum plants were sown.
Sedum roof construction components of a sedum green roof a sedum green roof is a build up of component layers that sit on top of a conventional roof surface.
We designed and built our own sedum roof on a 5m wide carport.
The roof can be installed in four easy steps providing an instant extensive sedum roof on the day of installation because it is delivered with 90 95 mature sedum plant cover in self contained fully complete trays including drainage layer filter layer and planting.
An all purpose soil less peat free potting mix is fine for growing herbs and other edibles but mix in plenty of perlite to both improve drainage and save on weight.
Single course construction consisting of a vegetation support layer with a drainage and filter function for all types of construction a root resistant membrane and protection layer are necessary to protect the waterproofing root resistant membrane.
Now comes the growing medium which for a sedum roof should be at least 8cm 3in deep and for a roof of wildflowers herbs salad and strawberries at least 15cm 6in deep.
An extensive green roof or sedum roof is a roof with vegetation that is more or less self perpetuating and that can further develop and maintain itself.